RH Genotype Matched RBC Transfusions

This is a Phase 1/2 trial in patients with Sickle Cell Disease requiring chronic red cell transfusions. RH genotyped donor units will be obtained from the New York Blood Center. Patients will be matched with donor units whose RH genotypes predict no foreign Rh protein exposure to the patient. This will provide red cell matching at a level above the current standard of care (serologic C, E, and K matching). Patients will receive RH matched red cells for the duration of their chronic transfusion therapy or up to three years, whichever is shorter. In the pilot phase, we have determined it is feasible to identify RH matched donor units for the patient's RH genotype for every scheduled transfusion. We will now continue to show feasibility as well as determine efficacy by monitoring Rh alloantibody formation. For subjects with a history of stroke/recurrent transient ischemic attack or other indication who require tight control of Hb S, and RH genotyped blood is not available, standard of care serologic matched blood would be administered rather than delaying transfusion and risking higher Hb S level. For all subjects, standard of care serologic matched blood would be administered rather than delaying transfusion beyond 7 days.